This invention relates to an energy saving system for controlling the temperature of buildings, particularly of animal raising establishments, comprising compartmentalized areas for a plurality of living animals, which system is also suitable for reducing the spread of infection between the individual compartments in said establishment.
It is known that the air in buildings which serve for containing a plurality of living animals contains waste products due to exhaled carbon dioxide and increased humidity. Added to these in animal storage structures are gases and vapors from decomposition of animal waste products, e.g. fecal matter and urine. The elimination of the vapors was made before exclusively through an exchange of air (by natural or artifical ventilation). The fresh air that was introduced had to be heated in the winter or during cold weather at other times of the year. The largest part of the heating energy is spent essentially for heating the incoming fresh air, whereas the heat content of the exhausted air is lost to the atmosphere.
Systems are known in which a heat exchange is carried out between the introduced and exhausted air, whereby an about 15-30% reduction in the energy required for heating is obtained. This method is, however, thermodynamically not sufficiently effective, since the heat exchange takes place at the lower temperature level of the exhausted air and more heat is required to raise the temperature of the incoming air to an acceptable level.
A known solution is described in Hungarian Pat. No. 174,791, according to which water vapor (steam) that is created in the building is removed through condensation, not by exhaust. The heat energy content of the water vapor (steam) amounts to about 2,350-2,500 kJ/kg. According to Hungarian Pat. No. 182,321, a heat pump is employed for the condensation and the heat content of the water vapor (steam) can be utilized at an effective temperature level with the aid of that pump. This system requires only an amount of fresh air which is required for removing the contaminating gases. In the case of poultry storage this amounts to, e.g. in the case of current norms for air exchange, a required quantity of fresh air of 2.5-4 cubic meter/kg live weight/hr in the winter, whereas the fresh air feed in the case of the water vapor condensation solution becomes lowered to 0.3-0.5 cubic meter/kg live weight/hr. According to experience a part of the contaminated gases condenses together with the water vapor (steam). It can be demonstrated that with such methods the required amount of primary energy can be lowered by about 60-75%, depending on the variety of animal. The water vapor condensation system is used in the summer to make the inside temperature tolerable by cooling, so that the production results can be maintained at optimum levels.
Further energy savings can be achieved when a suitable solution is found for the elimination of the decomposition gases or for reducing the proportion of such gases in the air of the area in question. Such method is described in Hungarian patent application No. 1228/84, according to which a substantial part of the contaminated exhaust gases is removed by chemical filtration. The water vapors obtained in that manner, contain a negligibly low amount of exhaust gas content, but have a heat content, can be recirculated into the area as pure air at a temperature of about 20-26 degrees Centigrade.
The amount of fresh air needed can be considerably reduced, but not entirely eliminated, by means of the aforementioned solutions. The ideal condition would be when only the oxygen requirement would have to be introduced from the outside. Even the reduced amount of air that is introduced into the area contains more oxygen than is necessary for the breathing of the animals.
Recently, in the case of raising and housing, economic considerations raise problems in addition to that of achieving energy savings. One such problem is that, due to the danger of infection, different age groups cannot be kept in the same growing plant so that the utilization of the plants becomes uneconomical.
The present invention aims at providing a solution to the aforementioned problems and to create a production system which, in addition to energy savings, realizes a better utilization of the plant space and a more economical organization of operations in which the raising of different age groups can be achieved in a single poultry raising plant, without any danger.